THE FATE OF RESIDUAL DEFECTS FOLLOWING CAROTID ENDARTERECTOMY DETECTED BY EARLY POSTOPERATIVE DUPLEX ULTRASOUND

BACKGROUND: The purpose of this study is to evaluate the results of co lor-flow duplex ultrasound (CFB) soon after carotid endarterectomy (CE A) to determine the incidence of residual abnormalities and their effe ct on subsequent outcome and management. METHODS: We reviewed 318 cons ecutive CEAs performed over a 48 month-period, Of these, 206 were foll owed up with CFD, 195 prior to discharge and 11 at first follow-up (wi thin 9 weeks). Patients (43) followed up with only oculoplethysmograph y (OPG) car those with no OPG or CFD (69) were excluded from the study , All CEAs were performed under general anesthesia with routine shunti ng and patch angioplasty. RESULTS: Twelve of the 206 studies (5.8%) we re abnormal, Two patients with an abnormal CFD sustained perioperative stroke, both of whom had distal intimal lesions of >60% diameter sten osis by velocity criteria, Four patients had >60% stenosis and were re operated upon to correct technical errors, The remaining 6 patients ar e asymptomatic, Four had residual lesions of <60% stenosis, three of w hich have returned to normal on subsequent CFD, Two residual lesions h ad >60% stenosis; one returned to normal by CFD and the other remains abnormal at 10 months, In the group of 199 normal postoperative CFD st udies, there were no strokes, deaths, or redo procedures (0%, 95% conf idence interval 0% to 1.54%) compared with a combined 50% rate (6 of 1 2) of either stroke (2 of 12) or redo procedure (4 of 12) when the pos toperative CFD was abnormal (95% confidence interval 22.3% to 77.7%, P < 0.0001), During the study period the CEA stroke rate was 0.9% (3 of 318), with a combined stroke-mortality rate of 1.3% (4 of 318). CONCL USIONS: Early postoperative CFD identified residual abnormalities in 5 .8% of carotid endarterectomies despite a low overall stroke mortality rate, One half of these abnormalities resulted in stroke or required operative correction, Color-flow duplex ultrasound is useful in identi fying residual abnormalities following CEA and should be considered fo r intraoperative use.